public class Solution62 {
    public int uniquePaths(int m, int n) {
        long ans=1;
        for (int i=1;i<=Math.min(m,n)-1;i++){
            ans=ans*(n+m-1-i)/i;
        }
        return (int)ans;
    }

    public static void main(String[] args) {
        System.out.println(new Solution62().uniquePaths(1,100));
    }
}
